Video format

MP4 converter

An .mp4 file is a multimedia container that bundles compressed video, audio, subtitles, and chapter data into a single stream-friendly package. It is the default delivery format for nearly every phone, camera, and video platform, which makes .mp4 the safest target when a clip has to play everywhere.

Private for supported formats — processed in your browser

Convert supported files

Runs on your device

Drop MP4 files here

Batch files can each use a different output. Nothing uploads for local conversions.

Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.

Where MP4 comes from

MP4 was standardized in 2001 as ISO/IEC 14496-14, borrowing its atom-based internal structure directly from Apple's QuickTime file format. Later revisions folded in newer codecs such as H.265 and AV1, keeping the container relevant across two decades of compression research.

How MP4 works

Typically carries H.264/AVC or H.265/HEVC video with AAC audio, though the box structure also accepts AV1, MP3, and timed-text tracks
The container is codec-agnostic: the .mp4 wrapper only indexes and interleaves samples, while picture quality is decided entirely by the encoder inside
Moving the moov index atom to the front of the file ('faststart') lets playback begin before the download finishes
Fragmented MP4 (fMP4) splits media into short movie fragments, the layout used by DASH and modern HLS streaming
Common Encryption (CENC) lets DRM systems such as Widevine and FairPlay protect tracks without changing the container

When to use MP4

Publishing video to the web, social media, or a client who has not specified a format
Recording on phones and drones, most of which write .mp4 natively
Re-wrapping MKV or MOV footage so it plays on smart TVs and game consoles
Serving as the source for GIF or poster-frame extraction, since every decoder handles it

Strengths and limitations

Strengths

Plays natively in every modern browser, operating system, and mobile device
Streams efficiently once faststart or fragmentation is applied
Supports codecs from H.264 through AV1 within the same wrapper
Lower container overhead than AVI or Matroska for typical files

Limitations

Fewer track, attachment, and chapter features than Matroska
The dominant codecs inside it, H.264 and H.265, carry patent licensing costs for encoder vendors
A damaged moov atom can render an otherwise intact recording unplayable

Compatibility

Every current browser, including Chrome, Firefox, Safari, and Edge, plays H.264 .mp4 files without plugins, and hardware decoding is ubiquitous on phones and televisions. Files using HEVC inside the container are the main exception: Apple devices handle them well, while Firefox depends on the operating system's decoder.

iTunes-style metadata atoms (title, artist, cover art) plus XMP and per-track language tags; ID3 is not native to the container.